JP7144002B2 - Phosphor, phosphor composition using the same, and light-emitting device, lighting device, and image display device using the same - Google Patents

Description

TECHNICAL FIELD The present invention relates to novel phosphors, phosphor compositions using the same, and light-emitting devices, lighting devices, image display devices, and the like using these.

2. Description of the Related Art In recent years, in response to the trend toward energy saving, there is an increasing demand for lighting, backlights, and the like using LEDs in devices using light-emitting devices such as image display devices and lighting devices. As LEDs used for these applications, white-light-emitting LEDs that emit white light by combining an LED chip that emits light in the near-ultraviolet or short-wavelength visible region and a phosphor are becoming popular. As such white light emitting LEDs, those using a phosphor that emits yellow light using blue light emitted by a blue LED chip as excitation light are mainly used. In recent years, attempts have also been made to use a phosphor that emits blue light, a phosphor that emits green light, or a phosphor that emits red light. This type of light-emitting device is required to have excellent light-emitting properties, and phosphors used therein are also desired to have higher light-emitting properties.

As a green phosphor, for example, Patent Document 1 discloses a sialon phosphor containing an alkaline earth element. As a yellow or orange phosphor, for example, Patent Document 2 discloses an α-sialon phosphor represented by a composition formula of Sr _1.11 Al _2.25 Si _9.75 N ₁₆ :Eu _0.02 . .

In addition, Li-containing phosphors are being studied for the purpose of improving light emission characteristics. As a green phosphor containing Li, for example, Patent Document 3 discloses a stress-stimulated strontium aluminate material containing Li. Further, for example, Patent Document 4 discloses a Li ₁ Ba ₂ Al ₁ Si ₇ N ₁₂ :Eu ²⁺ phosphor. As a red phosphor containing Li, for example, Patent Document 5 discloses a solid solution of CaAlSiN ₃ :Eu ²⁺ and LiSi ₂ N ₃ . Furthermore, Patent Document 6, for example, discloses an SLA phosphor represented by a composition of SrLiAl ₃ N ₄ :Eu ²⁺ .

WO2011/016486A1 JP 2009-256558 A JP 2015-67799 A WO2014/003076A1 WO2006/126567A1 WO2013/175336A1

As described above, phosphors of various colors have been developed, but there is a strong demand for phosphors with improved emission characteristics.

The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a novel phosphor that emits green to yellow light in the near-ultraviolet or short-wavelength visible region, and a phosphor composition using the same. Another object of the present invention is to provide a light-emitting device, a lighting device, an image display device, and the like using the phosphor described above.

The present inventors have made intensive studies to search for new phosphors in order to solve the above problems. The present invention has been completed by discovering a novel phosphor that emits light at .

That is, the present invention provides various specific aspects shown below.
<1> M element, A element, Li, and C element (where M element is an activating element, A element is at least one element selected from the group consisting of Ca, Sr, and Ba, C element is Al and/or Ga) and further comprising a crystal phase containing N and/or O, wherein the crystal phase has a lattice constant satisfying the following range.
7.10≦lattice constant a≦8.68
7.10≤lattice constant b≤8.68
2.86×n≦lattice constant c≦3.49×n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28 Note that the ranges of lattice constants c specified by n may overlap.)

<2> The phosphor according to <1>, wherein at least Li and C elements are present in the same crystal site and the crystal system is a tetragonal system.
<3><1> or <2>, further comprising Mg and/or E element (where E element is at least one element selected from the group consisting of Si and Ge) phosphor.

<4> The phosphor according to <3>, wherein the crystal phase includes a crystal phase represented by the following formula [1].
M _a A _1-a Li _b-d1 C _c-d2-e Mg _d1+d2 E _e N _f O _g [1]
(In formula [1] above, a, b, c, d1, d2, e, f, and g are values that independently satisfy the following formula.
0<a≦0.2
1.0≤b≤3.5
1.0≤c≤4.0
0≦d1≦3.5
0≤d2≤4.0
0≤e≤4.0
0≤f≤5.0
0≤g≤5.0
4.0≤b+c≤5.0
4.0≤f+g≤5.0
0≦b−d1
0≦c−d2−e)

<5> In the above formula [1], 0 ≤ d1 ≤ 0.6, 0 ≤ d2 ≤ 0.6, and 0 ≤ e ≤ 1.0. Phosphor.
<6> In the above formula [1], 4.5 ≤ b + c ≤ 5.0, 0 ≤ d1 + d2 ≤ 1.0, and 4.5 ≤ f + g ≤ 5.0 <4 > or the phosphor according to <5>.

<7> The phosphor according to any one of <1> to <6>, including a crystal phase represented by the following formula [2].
M _a' A _m/na' Li _x-y1 C _4-x-y2-z Mg _y1+y2 E _z N _{4+2m/n-2x+y1-y2+z} O _{2x-y1+y2-z-2m/n} [2]
(In formula [2] above, a', m, n, x, y1, y2, and z are values that independently satisfy the following formula.
0<a′≦0.2×m/n
4/5≦m/n≦8/9
m/n≤x≤2+m/n
0≤y1≤0.6
0≤y2≤0.6
0≤y1+y2≤1.0
0≤z≤1.0
0≦x−y
0≦4-xy2-z)

<8> Any one of <1> to <7>, wherein the M element contains at least one element selected from the group consisting of Eu, Ce, Pr, Sm, Tb, Dy and Yb The phosphor according to the item.
<9> n is any one integer selected from 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, and 28 <1> ~ The phosphor according to any one of <8>.
<10> In the above formula [2], 22/27 ≤ m/n ≤ 7/8, and 0.5 × m/n + 0.5 × (2 + m/n) ≤ x ≤ 2 + m/n The phosphor according to any one of <7> to <9>.
<11> The fluorescence according to any one of <7> to <10>, wherein 0 ≤ y1 + y2 ≤ 0.1 and 0 ≤ z ≤ 0.1 in the above formula [2] body.

<12> The phosphor according to any one of <1> to <11>, wherein the M element contains Eu, the A element contains Sr, and the C element contains Al.
<13> The phosphor according to any one of <3> to <12>, wherein the E element contains Si.
<14> The phosphor according to any one of <1> to <13>, wherein n is an integer selected from 6, 7, 13, 17, and 23.
<15> In the above formula [2], 14/17 ≤ m/n ≤ 6/7 and 0.25 × m/n + 0.75 × (2 + m/n) ≤ x ≤ 2 + m/n The phosphor according to any one of <7> to <14>.
<16> Any one of <3> to <15>, wherein the M element is Eu, the A element is Sr, the C element is Al, and the E element is Si. Phosphor.

<17> In the above formula [2], n is 6, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n The phosphor according to any one of >.
<18> The phosphor according to <17>, wherein m is 5 and n is 6 in the above formula [2].

<19> In the above formula [2], n is 7, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n The phosphor according to any one of >.
<20> The phosphor according to <19>, wherein m is 6 and n is 7 in the above formula [2].

<21> In the above formula [2], n is 13, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n The phosphor according to any one of >.
<22> The phosphor according to <21>, wherein m is 11 and n is 13 in the above formula [2].

<23> In the above formula [2], n is 17, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n The phosphor according to any one of >.
<24> The phosphor according to <23>, wherein m is 14 and n is 17 in the above formula [2].

<25> In the above formula [2], n is 23, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n The phosphor according to any one of >.
<26> The phosphor according to <25>, wherein m is 19 and n is 23 in the above formula [2].

<27> Any one of <1> to <26>, further comprising F and/or Cl, wherein the total content of F and Cl in terms of the amount of elements is 5000 ppm or less. Phosphor.
<28> A phosphor composition comprising the phosphor according to any one of <1> to <27>, wherein the phosphor is contained in an amount of 20% by mass or more relative to the total amount.

<29> At least an excitation light source that emits light in the near-ultraviolet or short-wavelength visible region, and a phosphor that converts at least part of the light emitted by the excitation light source into a different emission spectrum, wherein the phosphor is the claim A light-emitting device comprising at least the phosphor according to any one of claims 1 to 27 and/or the phosphor composition according to claim 28.
<30> A lighting device comprising the light emitting device according to <29>.
<31> An image display device comprising the light emitting device according to <29>.

According to the present invention, a novel phosphor having a crystal structure different from that of conventional phosphors and emitting green to yellow light in the near-ultraviolet or short-wavelength visible region, and a phosphor composition using the same are provided. realizable. Due to its emission properties (excitation spectrum, emission spectrum, emission color, emission efficiency), this new phosphor is particularly useful in white-emitting LED applications. A light-emitting device containing the novel phosphor of the present invention, and a lighting device and an image display device containing this light-emitting device are highly efficient and of high quality.

It is a figure which shows Farey tree of the fluorescent substance of this invention. 4 is a graph showing the excitation spectrum and emission spectrum of the phosphor of Reference Example 1. FIG. 4 is a graph showing the emission spectrum of the phosphor of Example 1. FIG. 4 is a graph showing the excitation spectrum and emission spectrum of the phosphor of Example 2. FIG. 10 is a graph showing emission spectra of Example 3. FIG. 4 is a graph showing the excitation spectrum and emission spectrum of the phosphor of Example 4. FIG. 10 is a graph showing the emission spectrum of Example 5. FIG. 4 is a graph showing the relationship between the n value and the lattice constant a in Examples 1 to 5 and Reference Example 1. FIG. 4 is a graph showing the relationship between the n value and the lattice constant c in Examples 1 to 5 and Reference Example 1. FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. The following embodiments are examples (representative examples) of embodiments of the present invention, and the present invention is not limited to these. In addition, the present invention can be arbitrarily changed and implemented without departing from the gist thereof. In this specification, the numerical range represented by "-" means a range including the numerical values before and after "-" as lower and upper limits. For example, a numerical range of "1 to 100" includes both the lower limit of "1" and the upper limit of "100". The notation of other numerical ranges is the same.

Further, in the compositional formulas of the phosphors in this specification, each compositional formula is delimited by a comma (,). When a plurality of elements are listed separated by commas (,), it indicates that one or more of the listed elements may be contained in any combination and ratio. For example, the composition formula “(Ca, Sr, Ba) Al ₂ O ₄ :Eu” is composed of “CaAl ₂ O ₄ :Eu”, “SrAl ₂ O ₄ :Eu” and “BaAl ₂ O ₄ :Eu”. and "Ca _1-x Sr _x Al ₂ O ₄ :Eu", "Sr _1-x Ba _x Al ₂ O ₄ : Eu", and "Ca _1-x Ba _x Al ₂ O ₄ : Eu", "Ca _{1-xy Sr x} Bay Al ₂ O ₄ :Eu" (where 0<x<1, 0<y<1, 0<x+y<1 in these formulas) It is assumed that the

<Phosphor>
The phosphor of the present embodiment includes M element, A element, Li, and C element (where M element is an activating element, and A element is at least one element selected from the group consisting of Ca, Sr, and Ba, C element is Al and/or Ga), and further includes a crystal phase containing N and/or O, wherein the lattice constant of the crystal phase satisfies the following range.
7.10≦lattice constant a≦8.68
7.10≤lattice constant b≤8.68
2.86×n≦lattice constant c≦3.49×n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28 Note that the ranges of the lattice constant c specified by the n value may overlap.)

Here, in the phosphor, the number of A elements in the c-axis direction in the unit cell is m, the number of C elements (N, O) ₄ in the c-axis direction is n, the composition ratio of M elements is a, and the composition of Li is It can also be said to be represented by the general formula M _a A _m/na Li _x C _4-x N _{4 +2m/n-2x} O _2x-2m/n , where x is the ratio.

Note that the phosphor represented by the general formula includes all substances existing at a certain m/n value. m/n = 1/1, 8/9, 7/8, 13/15, 6/7, 17/20, 11/13, 16/19, 5/6, 19/23, 14/17, 23/ 1/1 crystal, 8/9 crystal, 7/8 crystal, 13/15 crystal, 6/7 crystal , 17/20 crystal, 11/13 crystal, 16/19 crystal, 5/6 crystal, 19/23 crystal, 14/17 crystal, 23/28 crystal, 9/11 crystal, 22/27 crystal, 13/16 crystal , 17/21 crystal, and 4/5 crystal, respectively.
In addition, substances existing at a certain m/n value and relationships between them can also be explained by Farey tree. FIG. 1 shows a Farey tree of the phosphor of this embodiment. Henceforth, the substance group of this invention may be called FT substance group.
This FT substance group exhibits different crystal structures depending on the ratio (:m/n) of the number of stacked layers of the M element in the c-axis direction and the number of stacked layers of the C element (N, O) ₄ in the c-axis direction. Also, the ratio of N and O is determined according to the composition ratio (x) of Li and C elements. In the FT substance group, the initial structure of another m/n crystal can be derived from the crystal structure of one m/n crystal. This FT substance group is a substance group having a crystal structure in which n number of C elements (N, O) ₄ are stacked in the c-axis direction. Therefore, the c-axis lattice constant of each substance can be roughly arranged to be n times the c-axis lattice constant of the 1/1 crystal. Each element will be described in detail below.

M element is an activating element and includes europium (Eu), manganese (Mn), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), terbium (Tb), dysprosium (Dy), represents one or more elements selected from the group consisting of holmium (Ho), erbium (Er), thulium (Tm) and ytterbium (Yb); The M element preferably contains at least Eu, more preferably Eu.

Furthermore, all or part of Eu may be substituted with one or more elements selected from the group consisting of Ce, Pr, Sm, Tb, Dy and Yb. That is, the M element preferably contains Eu and at least one element selected from the group consisting of Ce, Pr, Sm, Tb, Dy and Yb. From the viewpoint of emission quantum efficiency, Eu and Ce are more preferable. That is, the M element is more preferably Eu and/or Ce, more preferably Eu. The content ratio of Eu to the entire M element is not particularly limited, but is preferably 50 mol % or more, more preferably 70 mol % or more, and particularly preferably 90 mol % or more.

The A element represents at least one element selected from the group consisting of calcium (Ca), strontium (Sr), and barium (Ba). The A element preferably contains Sr, more preferably Sr. Incidentally, the A element may be partially substituted with a divalent metal element other than the alkaline earth metal element, such as zinc (Zn).

Li represents lithium. Li may be partially substituted with other monovalent elements such as sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and the like.

C element represents aluminum (Al) and/or gallium (Ga). The C element preferably contains Al, more preferably Al. Note that C elements are other trivalent elements such as boron (B), indium (In), scandium (Sc), yttrium (Y), lanthanum (La), gadolinium (Gd), lutetium (Lu), etc. may be partially substituted with

In addition to the minimum constituent elements described above, the phosphor of this embodiment includes other elements such as fluorine atoms (F), chlorine atoms (Cl), bromine atoms (Br), and halogen atoms such as iodine atoms (I). may contain Halogen atoms are considered not only to be mixed as impurities in the raw material metal, but also to be introduced during the manufacturing process such as the pulverization process or the nitriding process. It tends to be included with a high probability.

The lattice constant a of the phosphor of this embodiment is usually 7.10 Å or more, preferably 7.49 Å or more, more preferably 7.65 Å or more, and usually 8.68 Å or less, preferably 8.28 Å or less, and more It is preferably 8.12 Å or less.

Furthermore, the lattice constant b is usually 7.10 Å or more, preferably 7.49 Å or more, more preferably 7.65 Å or more, and usually 8.68 Å or less, preferably 8.28 Å or less, more preferably 8.12 Å It is below.

Furthermore, the lattice constant c is usually 2.86×nÅ or more, preferably 3.02×nÅ or more, more preferably 3.08×nÅ or more, and usually 3.49×nÅ or less, preferably 3.33. x n Å or less, more preferably 3.27 x n Å or less.

n is usually 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, 28, preferably 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, 28, more preferably 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, 28 and more preferably 6, 7, 13, 15, 17, 19, 20, 23, 28, still more preferably 6, 7, 13, 17, 19, 20, 23, particularly preferably 6, 7, 13 , 17, 23.

The phosphor of this embodiment has a tetragonal crystal structure. Moreover, in the crystal structure, at least Li and C elements exist in the same crystal site.

The phosphor of this embodiment may further contain Mg and/or E element (where E element is at least one element selected from the group consisting of Si and Ge).

Mg represents magnesium. Mg may be partially substituted with a divalent metal element other than alkaline earth metal elements, such as zinc (Zn).

The E element represents at least one element selected from the group consisting of silicon (Si) and germanium (Ge). The E element preferably contains Si, more preferably Si. The E element may be partially substituted with other tetravalent elements such as tin (Sn), titanium (Ti), zirconium (Zr), hafnium (Hf), and the like.

The phosphor of this embodiment preferably contains a crystal phase having a composition represented by the following formula [1].
M _a A _1-a Li _b-d1 C _c-d2-e Mg _d1+d2 E _e N _f O _g [1]
(In formula [1] above, a, b, c, d1, d2, e, f, and g are values that independently satisfy the following formula.
0<a≦0.2
1.0≤b≤3.5
1.0≤c≤4.0
0≦d1≦3.5
0≤d2≤4.0
0≤e≤4.0
0≤f≤5.0
0≤g≤5.0
4.0≤b+c≤5.0
4.0≤f+g≤5.0
0≦b−d1
0≦c−d2−e)

a represents the content of the M element, the range is usually 0 < a ≤ 0.2, the lower limit is preferably 0.001, more preferably 0.02, and the upper limit is It is preferably 0.15, more preferably 0.1.

b represents the content of Li, the range is usually 1.0 ≤ b ≤ 3.5, the lower limit is preferably 1.56, more preferably 2.14, further preferably 2.73 , particularly preferably 2.75, most preferably 3.22. Also, the upper limit thereof is preferably 3.47, more preferably 3.45, even more preferably 3.44, particularly preferably 3.43.

c represents the content of element C, and its range is usually 1.0≦c≦4.0, and the lower limit is preferably 1.25, more preferably 1.29, and still more preferably 1.25. 31, particularly preferably 1.33, and its upper limit is preferably 3.32, more preferably 2.68, even more preferably 2.04, particularly preferably 1.55.

d1 represents the amount of Mg substituted for Li, and its range is usually 0≦d1≦3.5, and its upper limit is preferably 1.5, more preferably 0.6, further preferably 0.5. 5, particularly preferably 0.1.

d2 represents the substitution amount of Mg for Al, and its range is usually 0≤d2≤4.0, and its upper limit is preferably 2.0, more preferably 0.6, further preferably 0.6. 5, particularly preferably 0.1.

e represents the substitution amount of E element for Al, the range is usually 0 ≤ e ≤ 4.0, the upper limit is preferably 2.0, more preferably 0.6, further preferably 0 .5, particularly preferably 0.1.

f represents the content of N, the range is usually 0 ≤ f ≤ 5.0, the upper limit is preferably 4.50, more preferably 3.71, further preferably 2.45, It is more preferably 1.22, particularly preferably 1.21, and most preferably 0.24.

g represents the content of O, the range is usually 0 ≤ g ≤ 5.0, the lower limit is preferably 1.13, more preferably 2.29, still more preferably 3.46, especially Preferably 3.50, most preferably 4.43.

The range of b + c is usually 4.0 ≤ b + c ≤ 5.0, preferably 4.5 ≤ b + c ≤ 5.0, and the lower limit is more preferably 4.57, further preferably 4.62, especially It is preferably 4.67, and its upper limit is more preferably 4.91, still more preferably 4.87, particularly preferably 4.86.

The range of f + g is usually 4.0 ≤ f + g ≤ 5.0, preferably 4.5 ≤ f + g ≤ 5.0, and the lower limit is more preferably 4.57, further preferably 4.62, especially It is preferably 4.67, and its upper limit is more preferably 4.91, still more preferably 4.87, particularly preferably 4.86.

In the above formula [1], it is preferable that 0≦d1≦0.6, 0≦d2≦0.6, and 0≦e≦1.0.

Moreover, in the above formula [1], it is preferable to further satisfy the following formula.
4.5≤b+c≤5.0
0≦d1+d2≦1.0
4.5≤f+g≤5.0

The range of d1+d2 is preferably 0≤d1+d2≤1.0, and the upper limit thereof is more preferably 0.6, still more preferably 0.5, and particularly preferably 0.1.

In the phosphor of this embodiment, it is preferable that the crystal phase includes a crystal phase having a composition represented by the following formula [2].
M _a' A _m/na' Li _x-y1 C _4-x-y2-z Mg _y1+y2 E _z N _{4+2m/n-2x+y1-y2+z} O _{2x-y1+y2-z-2m/n} [2]

In the above formula [2], the M element, A element, Li, C element, Mg, E element, N, and O have the same meanings as those explained in the above formula [1].

In the above formula [2], a′, m, n, x, y1, y2, and z are each independently values satisfying the following formulas.
0<a′≦0.2×m/n
4/5≦m/n≦8/9
m/n≤x≤2+m/n
0≤y1≤0.6
0≤y2≤0.6
0≤y1+y2≤1.0
0≤z≤1.0
0≦x−y
0≦4-xy2-z

a' represents the content of the M element, the range is usually 0 < a' ≤ 0.2 × m / n, the lower limit is preferably 0.001 × m / n, more preferably 0 02×m/n, and its upper limit is preferably 0.15×m/n, more preferably 0.1×m/n.

m/n represents the content of A, the range is usually 4/5 ≤ m/n ≤ 8/9, the lower limit is preferably 17/21, more preferably 22/27, further preferably is 23/28, particularly preferably 14/17. Also, the upper limit is preferably 7/8, more preferably 13/15, still more preferably 6/7.

x represents the content of Li, the range is usually m/n≦x≦2+m/n, the lower limit is m/n, preferably 0.75×m/n+0.25×(2+m /n), more preferably 0.5 x m/n + 0.5 x (2 + m/n), still more preferably 0.25 x m/n + 0.75 x (2 + m/n), particularly preferably 0.05 x m /n + 0.95 x (2 + m/n), and its upper limit is 2 + m/n, preferably 0.25 x m/n + 0.75 x (2 + m/n), more preferably 0.5 x m/n+0.5×(2+m/n), more preferably 0.75×m/n+0.25×(2+m/n), particularly preferably 0.95×m/n+0.05×(2+m/n) be.

y1 represents the substitution amount of Mg for Li, the range is usually 0≦y1≦0.6, and the upper limit is preferably 0.5, more preferably 0.1.

y2 represents the substitution amount of Mg for Al, the range is usually 0≤y2≤0.6, and the upper limit is preferably 0.5, more preferably 0.1.

z represents the substitution amount of E for Al, the range is usually 0≦z≦1.0, and the upper limit is preferably 0.5, more preferably 0.1.

Moreover, in the above formula [2], it is preferable that 0≦y1+y2≦0.1 and 0≦z≦0.1.

Any content within the above range is preferable in terms of the emission characteristics of the resulting phosphor, particularly the emission luminance being good.

Specific examples of the phosphor represented by formula [1] or formula [2] include those shown in Tables 1 and 2, but are not particularly limited thereto.

<Physical properties of phosphor>
[Luminous color]
The emission color of the phosphor of this embodiment can be excited by light in the near-ultraviolet region to the blue region, such as wavelengths of 300 nm to 500 nm, by adjusting the chemical composition and the like. etc., it is possible to emit a desired emission color.

[Emission spectrum]
The phosphor of this embodiment preferably has the following characteristics when the emission spectrum is measured when excited with light having a wavelength of 400 nm. That is, the peak wavelength (maximum emission wavelength) in the above emission spectrum is usually 500 nm or longer, preferably 510 nm or longer, and more preferably 520 nm or longer. Also, the upper limit is usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. It is preferable that the emission spectrum is within the above range because the obtained phosphor exhibits a favorable green to yellow color.

[Half width of emission spectrum]
In the phosphor of this embodiment, the half width of the emission peak in the above emission spectrum is usually 100 nm or less, preferably 90 nm or less, more preferably 85 nm or less, and the lower limit thereof is usually 30 nm or more. Within the above range, when used in a light-emitting device such as a liquid crystal display device, a decrease in color purity is suppressed and the color reproduction range tends to be widened, which is preferable.

The excitation light source for exciting the phosphor of this embodiment with light having a wavelength of 400 nm is not particularly limited, but for example, a GaN-based LED can be used. As the excitation light source, for example, an ultraviolet (or violet) LED light emitting element or a blue LED light emitting element that emits light with a wavelength of 300 to 500 nm can be used. are known, and by adjusting the composition, it can be used as a light emitting source that emits light of a predetermined wavelength. The measurement of the emission spectrum of the phosphor of this embodiment and the calculation of its emission peak wavelength, peak relative intensity and peak half-value width are performed, for example, by using a 150 W xenon lamp as an excitation light source and multi-channel CCD detection as a spectrum measurement device. It can be performed using a fluorometer (manufactured by JASCO Corporation) equipped with a device C7041 (manufactured by Hamamatsu Photonics). For example, an LED light-emitting device can be manufactured using the phosphor of the present invention by known methods such as those described in JP-A-5-152609, JP-A-7-99345, and Japanese Patent Publication No. 2927279. can.

[Excitation wavelength]
The phosphor of this embodiment is excited in a wavelength range of usually 300 nm or more, preferably 350 nm or more, more preferably 380 nm or more, and usually 500 nm or less, preferably 490 nm or less, more preferably 480 nm or less, further preferably 460 nm or less. It has a peak (maximum absorption wavelength). In other words, the phosphor of this embodiment is normally excitable by light in the near-ultraviolet to blue region.

[Crystal system and space group]
The crystal system in the phosphor of this embodiment is Tetragonal. In addition, the space group in the phosphor of the present embodiment is not particularly limited as long as the average structure exhibits a repeating period of the above length (that is, a period in which the lattice constant c is within a predetermined range). Crystallography (Third, revised edition), Volume A SPACE-GROUP SYMMETRY", No. 85 (P 4/n) or No. 87 (I 4/m). Here, the lattice constant and space group can be obtained according to the usual method. Specifically, the lattice constant can be obtained by Rietveld analysis of the results of X-ray diffraction and neutron diffraction, and the space group is electron diffraction, X-ray diffraction using a single crystal, and It can be determined by analysis of neutron beam diffraction.

In the FT substance group of the present invention, the lattice constant changes by substituting its constituents with other elements or solid solution with activating elements. Atomic positions given by atomic coordinates do not change so much that chemical bonds between backbone atoms are broken.
In the present invention, at least claim 1 is satisfied, and the length of the chemical bond between atoms calculated from the lattice constant and atomic coordinates obtained by analyzing the results of X-ray diffraction or neutron diffraction is determined by each FT substance If the chemical bond length between atoms calculated from the lattice constant of the group and the atomic coordinates is within ±10%, it is judged to have the same crystal structure as the phosphor of the present invention.

<Manufacturing method of phosphor>
The method for producing the phosphor of the present embodiment is not particularly limited. , may be arbitrarily referred to as "A source".), a source of Li (hereinafter, may be arbitrarily referred to as "Li source"), and a source of C element (hereinafter, may be arbitrarily referred to as "C source"). ), and an E element raw material (hereinafter sometimes referred to as an “E source”) and a Mg raw material (hereinafter sometimes referred to as an “Mg source”) that are blended as necessary. ) and the like (mixing step) and firing the obtained mixture (firing step). In the following, for example, the raw material of element Eu may be referred to as "Eu source", and the raw material of element Sm may be referred to as "Sm source". The raw material of the element Al is sometimes referred to as "Al source", the raw material of element Si is sometimes referred to as "Si source", etc. The same applies to other elements.

[Phosphor raw material]
Phosphor raw materials such as M source, A source, Li source, C source, E source and Mg source are silicides, oxides, carbonates, nitrides, oxynitrides, halides (chlorides, fluorides ), acid fluorides, hydroxides, oxalates, sulfates, nitrates, organometallic compounds, precursor compounds thereof, and the like, and the type thereof is not particularly limited. As the phosphor raw material, one type can be used alone, and two or more types can be used in any combination and ratio. Among these, oxides, nitrides, halides, carbonates and silicides are preferred, and oxides, nitrides and halides are more preferred.

In addition, if necessary, the phosphor of the present embodiment may be synthesized in advance and mixed with the raw material mixture as a seed crystal (seed crystal). By using seed crystals in this way, crystallization and low-temperature synthesis are promoted, and there is a tendency to easily obtain a phosphor having a higher degree of crystallinity. Although the mixing ratio of the seed crystal is not particularly limited, it is preferably in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the phosphor raw material.

(M source)
Among the M sources that are activating elements, specific examples of the Eu source include _Eu2O3 , _{Eu2 ( SO4} ) ₃ , _{Eu2 ( C2O4} ) _3.10H2O , _{EuF3 ,} and _EuCl2 . , EuCl ₃ , Eu(NO ₃ ) _{3.6H 2} O, EuN, and EuNH, but are not particularly limited thereto. Among these, Eu ₂ O ₃ , EuF ₃ and EuN are preferred, and EuN is particularly preferred. On the other hand, specific examples of raw materials for other activating elements such as Sm sources, Tm sources, and Yb sources include compounds obtained by replacing Eu with Sm, Tm, Yb, etc. in the compounds given as specific examples of Eu sources. is mentioned.

(A source)
Specific examples of the Sr source among the A sources include SrO, Sr ₍ OH) _2.8H2O , SrCO3, Sr _{( NO3} ) ₂ , _SrSO4 , Sr _{( C2O4} ) _.H2O , Sr(OCOCH ₃ ) ₂ ·0.5H ₂ O, SrF ₂ , SrCl ₂ , Sr ₂ N, Sr ₃ N ₂ , SrNH and the like, but are not particularly limited thereto. Among these, SrO, SrCO ₃ , Sr ₂ N and Sr ₃ N ₂ are preferred. From the viewpoint of reactivity, it is preferable that the particle size is small and the purity is high from the viewpoint of luminous efficiency. On the other hand, specific examples of raw materials for other alkaline earth metal elements such as Ca sources and Ba sources include compounds in which Sr is replaced with Ca, Ba, etc. in the compounds given as specific examples of the Sr source. .

(Li source)
Specific examples of the Li source include Li ₂ O, LiOH, Li ₂ CO ₃ , LiNO ₃ , Li ₂ SO ₄ , LiF, LiCl, Li ₃ N, LiNH ₂ and hydrates of these compounds. , but not limited to these. Among these, Li ₂ O, Li ₂ CO ₃ and Li ₃ N are preferred. Moreover, from the viewpoint of luminous efficiency, one having high purity is preferable. On the other hand, in the case where Li is partially substituted with another monovalent element, specific examples of raw materials for the other monovalent element include, in each of the compounds given as specific examples of the Li source, Li being Na, Examples include compounds in which K, Rb, Cs, etc. are substituted. Note that the Li source may be Li alone.

(C source)
Among the C sources, specific examples of the Al source include AlN, _Al2O3 , Al(OH) ₃ , AlOOH, Al( _NO3 ) ₃ , _{AlF3 ,} AlCl3 and the like _, but are particularly limited to these. not. Among these, AlN and Al ₂ O ₃ are preferred. Moreover, from the viewpoint of reactivity, it is preferable that the particle size is small and the purity is high from the viewpoint of luminous efficiency. On the other hand, specific examples of the Ga source include compounds in which Ga is substituted for Al in each of the compounds given as specific examples of the Al source. In the case where Al or Ga is partially substituted with another trivalent element, specific examples of raw materials for the other trivalent element include Al in each of the compounds given as specific examples of the Al source. Compounds substituted with B, In, Sc, Y, La, Gd, Lu and the like can be mentioned. In addition, the Al source may be a simple substance of Al.

(Mg source)
Specific examples of Mg sources include MgO, Mg(OH) ₂ , MgCO ₃ , Mg(NO ₃ ) ₂ , MgSO ₄ , Mg(C ₂ O ₄ ).H ₂ O, Mg(OCOCH ₃ ) _2.0 . 5H ₂ O, MgF ₂ , MgCl ₂ and hydrates thereof, Sr ₂ N, Sr ₃ N ₂ , SrNH and the like, but are not particularly limited thereto. Among these, MgO, MgCO ₃ and Mg ₃ N ₂ are preferred. From the viewpoint of reactivity, it is preferable that the particle size is small and the purity is high from the viewpoint of luminous efficiency.

(E source)
Of the E sources, specific examples of Si sources include SiO ₂ and Si ₃ N ₄ , but are not particularly limited to these. A compound that becomes SiO ₂ can also be used. Specific examples of such compounds include SiO ₂ , H ₄ SiO ₄ , Si(OCOCH ₃ ) ₄ and the like. From the viewpoint of reactivity, Si ₃ N ₄ preferably has a small particle size and high purity from the viewpoint of luminous efficiency. Furthermore, it is preferable that the content of the carbon element, which is an impurity, is low. On the other hand, specific examples of the Ge source include compounds obtained by substituting Ge for Si in the compounds given as specific examples of the Si source. In the case where Si or Ge is partially substituted with another tetravalent element, specific examples of raw materials for the other tetravalent element include Si in each of the compounds given as specific examples of the Si source. Examples thereof include compounds in which Sn, Ti, Zr, Hf, etc. are substituted. It should be noted that the Si source may be Si alone.

The M source, A source, Li source, C source, Mg source and E source may be used singly, or two or more of them may be used in any combination and ratio. In general, the phosphor raw materials described above are weighed so as to obtain a phosphor having a desired composition, sufficiently mixed using a ball mill or the like, filled in a crucible, and fired under a predetermined temperature and atmosphere to obtain a mixture. By pulverizing and washing the baked product, the phosphor of the present embodiment having a desired composition can be obtained.

[Mixing process]
The method of mixing the phosphor raw materials is not particularly limited and may be performed by a known technique such as a dry mixing method or a wet mixing method. The dry mixing method includes, for example, a mixing method using a ball mill or the like. Further, as a wet mixing method, for example, a solvent such as water or a dispersion medium is added to the phosphor raw material described above, and the mixture is mixed using a ball mill, a mortar, a pestle, or the like to form a solution or slurry. It is a method of drying by spray drying, heat drying, natural drying, or the like. In addition, although water, an organic solvent, these mixed solvents, etc. are mentioned as a solvent or a dispersion medium, it is not specifically limited to these. For example, ester solvents such as methyl acetate, ethyl acetate, propyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; alcohol solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol and n-butanol; Hydrocarbon solvents such as hexane, cyclohexane, methylcyclohexane, and ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; or mixed solvents thereof; but not limited thereto. Among these, water, alcoholic solvents, and hydrogenated solvents are preferred. These can be used individually by 1 type or in combination of 2 or more types.

[Baking process]
The obtained mixture is filled in a heat-resistant container such as a crucible or a tray made of a material having low reactivity with each phosphor raw material. The material of the heat-resistant container used in such firing is not particularly limited as long as it does not impair the effects of the present embodiment.

The firing temperature during the firing step varies depending on the pressure, the external atmosphere, etc., but is usually in the range of 500° C. or higher and 2000° C. or lower. The highest temperature reached in this firing step is usually 600° C. or higher, preferably 700° C. or higher, more preferably 800° C. or higher, and usually 2000° C. or lower, preferably 1800° C. or lower. If the sintering temperature is too high, some of the elements contained in the matrix will be desorbed, many defects will be generated in the crystal, and the obtained crystal will tend to be colored. In some cases, it may be difficult to obtain a phosphor having the target phase as the main phase. Further, even if a very small amount of the desired crystal phase is obtained, if the firing temperature is too low, the element that serves as the luminescence center, such as the Eu element, will not be diffused in the crystal, which may reduce the quantum efficiency. In addition, if the firing temperature is too high, the elements constituting the target phosphor crystal are likely to volatilize, lattice defects are likely to be formed, or the crystal phase may be decomposed and another phase may be generated as an impurity. .

The pressure during the firing step varies depending on the firing temperature, the external atmosphere, etc., but is usually 0.1 MPa or more, and is usually 200 MPa or less, preferably 190 MPa or less.

The firing atmosphere in the firing step is arbitrary as long as the phosphor of the present embodiment can be obtained, but an atmosphere containing an inert gas (nitrogen, argon, etc.) is preferable. Specifically, a nitrogen gas atmosphere, a hydrogen-containing nitrogen atmosphere, or the like is preferable, and a nitrogen gas atmosphere is more preferable.

The firing time in the firing step varies depending on the temperature, pressure, external atmosphere, etc., but is usually 10 minutes or more, preferably 30 minutes or more, and usually 72 hours or less, preferably 24 hours or less. If the firing time is too short, grain formation and grain growth cannot be promoted, so it tends to be difficult to obtain a phosphor with good characteristics. Therefore, it tends to be difficult to obtain a phosphor with good characteristics due to defects being induced in the crystal structure due to atomic vacancies.

[Post-treatment process]
The baked product to be obtained is in the form of granules or lumps. This is pulverized, pulverized and/or classified into a powder of a predetermined size. Here, processing may be performed so that the median diameter (D50) is approximately 30 μm or less.
As a specific example of treatment, the composite is subjected to a sieve classification process with an opening of about 45 μm, and the powder that has passed through the sieve is sent to the next step, or the composite is subjected to a general method such as a ball mill, vibration mill, or jet mill. A method of pulverizing to a predetermined particle size using a pulverizer may be mentioned. In the latter method, excessive pulverization not only produces fine particles that easily scatter light, but also produces crystal defects on the particle surface, possibly causing a decrease in luminous efficiency.
Moreover, you may provide the process of wash|cleaning fluorescent substance (baked material) as needed. After the washing step, the phosphor is dried until all the attached water is gone, and is ready for use. Furthermore, if necessary, a dispersion/classification treatment may be performed to loosen aggregation.

From the viewpoint of obtaining a phosphor with excellent luminous properties, the content of impurities is preferably as low as possible. In particular, when a large amount of halogen elements such as Cl and F is contained, light emission tends to be inhibited. Therefore, the total content of Cl and F in terms of the amount of elements is preferably 5000 ppm or less, more preferably 3000 ppm. Below, more preferably below 2000ppm.

<Phosphor composition>
The phosphor of this embodiment can be used alone as a light-emitting material, but it can also be used as a phosphor composition by mixing it with other materials. That is, the phosphor composition may contain a substance different from the phosphor of this embodiment. When used as a phosphor composition, the content of the phosphor of this embodiment is preferably 20% by mass or more, more preferably 30% by mass or more, and still more preferably 40% by mass or more, relative to the total amount of the composition. . At this time, as a substance different from the phosphor of the present embodiment, a phosphor different from the phosphor of the present embodiment; addition reaction type silicone or condensation reaction type silicone resin, modified silicone resin, polycarbonate resin, epoxy resin, polyvinyl binder resins such as base resins, polyethylene resins, polypropylene resins, and polyester resins; sealing resins; glass; diffusing agents; thickeners;

<Light emitting device, etc.>
The phosphor of this embodiment and the phosphor composition using the same described above are suitably used as a light-emitting material for light-emitting devices such as lighting devices and image display devices. This type of light-emitting device includes at least an excitation light source that emits light in the near-ultraviolet or short-wavelength visible region, and a phosphor that converts at least part of the light emitted by the excitation light source into a different emission spectrum, As such a phosphor, the above-described phosphor of the present embodiment and a phosphor composition using the same may be used. As light-emitting devices such as lighting devices and image display devices, LED devices such as LED lighting devices and LED image display devices, EL devices such as EL lighting devices and EL image display devices, and fluorescent lamps are known. More specifically, white light emitting diodes, lighting fixtures including a plurality of white light emitting diodes, backlights for liquid crystal panels, and the like can be used, but the present invention is not particularly limited to these. Examples of image display devices include vacuum fluorescent display (VFD), field emission display (FED), plasma display panel (PDP), cathode ray tube (CRT), and liquid crystal display (LCD). not.

As the excitation light source, a light source that emits light in the near-ultraviolet region to the blue region with a wavelength of 300 to 500 nm matching the excitation peak (absorption maximum wavelength) of the phosphor of this embodiment is preferably used. Such light sources include light-emitting diodes (LEDs), laser diodes (LDs), semiconductor lasers, organic EL emitters (OLEDs), and the like, which emit light with a wavelength of 300 to 500 nm. As a result, the desired emission color such as green, yellowish green, yellow, and red can be efficiently emitted from the phosphor.

EXAMPLES The content of the present invention will be described in more detail below using examples, but the present invention is not limited by the following examples as long as it does not exceed the gist of the invention. Various production conditions and values of evaluation results in the following examples have the meaning of preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the preferable value of the upper limit or the lower limit. A preferable range may be a range defined by a combination of the above upper limit or lower limit and the values in the following examples or values between examples.

<Measurement method>
[Luminous properties]
Luminescent particles were collected, and the excitation emission spectrum and emission spectrum were measured using a Xe spectroscopic excitation device QE1100 (manufactured by Otsuka Electronics Co., Ltd.) and an emission detector MCPD-7700 (manufactured by Otsuka Electronics Co., Ltd.). Also, the emission peak wavelength and the half width of the emission peak were read from the obtained emission spectrum.
[Elemental analysis]
After selecting crystals by observation with a scanning electron microscope (SEM), each element was analyzed using an energy dispersive X-ray spectrometer (EDX).
[Crystal structure analysis]
The X-ray diffraction data of the single-crystal particles were measured with a single-crystal X-ray diffraction apparatus (Bruker AXS, D8 QUEST) equipped with an imaging plate and a graphite monochromator and using MoKα as an X-ray source. APEX2 was used for data collection and lattice constant refinement, and SADABS for X-ray shape absorption correction. Refinement of crystal structure parameters was performed using SHELXL ^- 97 and Jana2006 for the F2 data. VESTA was used for drawing the crystal structure.
<Synthesis conditions>
Li ₃ N, Li ₂ O, Mg ₃ N ₂ , Sr ₃ N ₂ , SrO, AlN, Al ₂ O ₃ , EuN, Eu ₂ O ₃ and EuF ₃ were used as phosphor raw powders, and SrF ₂ powder was used as flux. Using. The raw materials were weighed so as to have the masses shown in Table 3, then placed in a mortar and mixed until uniform to obtain raw material mixed powders of Examples 1 to 5 and Reference Example 1, respectively. From the raw material mixed powder thus obtained, the respective masses shown in Table 4 were fractionated and filled in containers made of molybdenum. All these operations were performed in a glove box filled with _N2 gas.

Next, each container was placed in a tubular furnace, N ₂ gas was passed through, and the temperature and holding time shown in Table 5 were applied. The fired container was introduced into a glove box filled with N ₂ gas, and the resulting product was pulverized in a mortar to obtain fired powders of Examples 1 to 5 and Reference Example 1, respectively.

[Reference example 1]
Columnar red particles were collected from the obtained sintered powder of Reference Example 1 (phosphor of Reference Example 1). The phosphor of Reference Example 1 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. = 8.07 [Å] and c = 3.31 [Å]. The phosphor of Reference Example 1 was the substance disclosed in Patent Document 6.
Next, the phosphor of Reference Example 1 was subjected to elemental analysis (EDX measurement). Table 6 shows the EDX measurement results and the calculated composition normalized by Sr+Eu=1. The detected elements were Sr, Mg, Al, Eu, N, O, F. Note that Li is not detected by EDX measurement.

Here, Table 7 shows the composition calculated using the following condition I based on the crystal structure of the 1/1 crystal. Similarly, Table 8 shows the composition calculated using the following conditions I, II and III based on the crystal structure of the 1/1 crystal.
Condition I: When Sr + Eu = 1, Li + Mg + Al = 4 Condition II: When Sr + Eu = 1, N + O = 4 Condition III: The values of N and O are the values that most satisfy the electrical neutrality condition.
(Eu is calculated as divalent. F may be slightly included,
not taken into account in the calculation. )

As shown in Table 8 _, the calculated composition _based on conditions I, _II and _{III was Sr0.96Li0.59Mg0.98Al2.43Eu0.04N3.85O0.15 .} The calculated composition suggests that the phosphor of Reference Example 1 may contain a trace amount of O, but is mostly a nitride. The reason for the large difference between the measured and calculated values of N and O is presumed to be oxidation of the particle surface. Also, from the calculated compositions determined from conditions I, II, and III, it is inferred that the substitution of Mg is mainly represented by the reaction formula of Li+Al→2Mg. Also, it is expected that the same amount of solid solution of Mg is allowed in other FT substance groups.

Next, the excitation/emission spectrum of the phosphor of Reference Example 1 is shown in FIG. The excitation spectrum of the phosphor of Reference Example 1 was obtained by monitoring the emission at 685 nm, and the emission spectrum was measured when excited using a light source of 492 nm. The phosphor of Reference Example 1 exhibited red light emission with an emission peak wavelength of 685 nm and a half width of 93 nm. Although the phosphor of Reference Example 1 showed strong light emission, it showed a wavelength with low visibility, which was not preferable.

[Example 1]
Fragment-like yellow particles were collected from the obtained fired powder of Example 1 (phosphor of Example 1). The phosphor of Example 1 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. It was a 6/7 crystal, with the crystal parameters and atomic coordinates indicated. The crystal composition when Eu was not included was Sr ₆ Li ₂₀ Al ₈ O ₂₈ , and when Sr=1, it was Sr ₁ Li _3.33 Al _1.33 O _4.67 .

Furthermore, the phosphor of Example 1 was subjected to elemental analysis (EDX measurement). Table 10 shows the EDX measurement results and the calculated composition normalized by Sr+Eu=6. The detected elements were Sr, Al, Eu, N, O and Cl. Note that Li was not detected by EDX measurement, and Cl is considered to have been mixed in during the production process of the sintered powder.

Here, Table 11 shows the calculated composition using the following condition I based on the crystal structure of the 6/7 crystal. Similarly, Table 12 shows the calculated composition using the following conditions I, II and III based on the crystal structure of the 6/7 crystal.
Condition I: When Sr + Eu = 6, Li + Al = 28 Condition II: When Sr + Eu = 1, N + O = 28 Condition III: The values of N and O are the values that most satisfy the electrical neutrality condition.
(Eu is calculated as divalent. Although some Cl may be contained,
not taken into account in the calculation. )
From Table 11, it was confirmed that the cation composition values obtained by structural analysis and the cation composition values obtained by EDX measurement were in good agreement.
Table 12 suggests that the phosphor of Example 1 is mostly an oxide, although it may contain a small amount of N.

Next, FIG. 3 shows an emission spectrum when the phosphor of Example 1 is excited with a light source of 365 nm. The phosphor of Example 1 exhibited yellow light emission with an emission peak wavelength of 571 nm and a half width of 80 nm.

[Example 2]
From the obtained fired powder of Example 2, tabular green particles were collected (phosphor of Example 2). The phosphor of Example 2 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. There were 11/13 crystals, accounting for the crystal parameters and atomic coordinates shown. The crystal composition when Eu was not included was Sr ₁₁ Li ₃₇ Al ₁₅ O ₅₂ , and when Sr=1, it was Sr ₁ Li _3.36 Al _1.36 O _4.73 .

FIG. 4 shows the excitation/emission spectrum of the phosphor of Example 2. As shown in FIG. The excitation spectrum of the phosphor of Example 2 was measured by monitoring the emission at 533 nm, and the emission spectrum was measured using a light source of 400 nm for excitation. The phosphor of Example 2 exhibited green light emission with an emission peak wavelength of 533 nm and a half width of 68 nm.

[Example 3]
The sintered powder of Example 3 was taken out from the container, and the plate-like green particles adhering to the wall surface of the container at this time were collected (phosphor of Example 3). The phosphor of Example 3 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. It was a 5/6 crystal, with the crystal parameters and atomic coordinates shown. The crystal composition when Eu was not included was Sr ₅ Li ₁₇ Al ₇ O ₂₄ , and when Sr=1, it was Sr ₁ Li _3.40 Al _1.40 O _4.80 .

Next, FIG. 5 shows an emission spectrum when the phosphor of Example 3 is excited with a light source of 365 nm. The phosphor of Example 3 exhibited green light emission with an emission peak wavelength of 533 nm and a half width of 66 nm.

[Example 4]
The sintered powder of Example 4 was taken out from the container, and the plate-like green particles adhering to the wall surface of the container at this time were collected (phosphor of Example 4). The phosphor of Example 4 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. It was a 19/23 crystal, with the crystal parameters and atomic coordinates shown. The crystal composition when Eu was not included was Sr ₁₉ Li ₆₅ Al ₂₇ O ₉₂ , and when Sr=1, it was Sr ₁ Li _3.42 Al _1.42 O _4.84 .

Furthermore, the phosphor of Example 4 was subjected to elemental analysis (EDX measurement). Table 16 shows the EDX measurement results and the calculated composition normalized by Sr+Eu=19. The detected elements were Sr, Mg, Al, Eu, N, O, F. Li was not detected by EDX measurement, and Mg was considered to have been mixed in during the production process of the sintered powder.

Here, Table 17 shows the calculated composition using the following condition I based on the crystal structure of the 19/23 crystal. Similarly, Table 18 shows the composition calculated using the following conditions I, II and III based on the crystal structure of the 19/23 crystal.
Condition I: Li + Mg + Al = 92 when Sr + Eu = 19 Condition II: N + O = 92 when Sr + Eu = 19 Condition III: The values of N and O are the values that best satisfy the electrical neutrality condition.
(Eu is calculated as divalent. F may be slightly included,
not taken into account in the calculation. )
From Table 17, it was confirmed that the cation composition values obtained by structural analysis and the cation composition values obtained by EDX measurement were in good agreement.
Table 18 suggests that the phosphor of Example 4 is mostly an oxide, although it may contain a small amount of N.

Next, FIG. 6 shows the excitation/emission spectrum of the phosphor of Example 4. As shown in FIG. The excitation spectrum of the phosphor of Example 4 was measured by monitoring the emission at 541 nm, and the emission spectrum was measured using a light source of 406 nm for excitation. The phosphor of Example 4 exhibited green light emission with an emission peak wavelength of 541 nm and a half width of 68 nm.

[Example 5]
The sintered powder of Example 5 was taken out from the container, and the aggregated green particles adhering to the wall surface of the container at this time were collected (phosphor of Example 5). The phosphor of Example 5 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. It was a 14/17 crystal, with crystal parameters and atomic coordinates shown. The crystal composition when Eu was not included was Sr ₇ Li ₂₄ Al ₁₀ O ₃₄ , and when Sr=1, it was Sr ₁ Li _3.43 Al _1.43 O _4.86 .

Furthermore, the phosphor of Example 5 was subjected to elemental analysis (EDX measurement). Table 20 shows the EDX measurement results and the calculated composition normalized by Sr+Eu=7. The detected elements were Sr, Mg, Al, Eu, N, O, F. Li was not detected by EDX measurement, and Mg was considered to have been mixed in during the production process of the sintered powder.

Here, Table 21 shows the composition calculated using the following condition I based on the crystal structure of the 14/17 crystal. Similarly, Table 22 shows the calculated composition using conditions I, II and III based on the crystal structure of the 14/17 crystal.
Condition I: When Sr + Eu = 7, Li + Mg + Al = 34 Condition II: When Sr + Eu = 7, N + O = 34 Condition III: The values of N and O are the values that most satisfy the electrical neutrality condition.
(Eu is calculated as divalent. F may be slightly included,
not taken into account in the calculation. )
From Table 21, it was confirmed that the cation composition values obtained by structural analysis and the cation composition values obtained by EDX measurement were in good agreement.
Table 22 suggests that the phosphor of Example 5 is mostly an oxide, although it may contain a small amount of N.

FIG. 7 shows the emission spectrum when the phosphor of Example 5 was excited with a light source of 365 nm. The phosphor of Example 5 exhibited green light emission with an emission peak wavelength of 529 nm and a half width of 69 nm.

<Comprehensive explanation>
[General lattice constant in FT substance group]
Table 23 shows the lattice constant a and the lattice constant c obtained from single crystal X-ray structural analysis for the phosphors of Reference Example 1 and Examples 1 to 5. Since the crystal structures of the phosphors of Reference Example 1 and Examples 1 to 5 belong to the tetragonal system, lattice constant a=lattice constant b.

FIG. 8 shows values of the lattice constant a of the phosphors of Reference Example 1 and Examples 1 to 5 with respect to the n value. The average value of lattice constant a was 7.8875 [Å].
Also, FIG. 9 shows values of the lattice constant c of the phosphors of Reference Example 1 and Examples 1 to 5 with respect to the n value. In addition, FIG. 9 shows an approximate straight line obtained by the method of least squares when the intercept is set to 0. In FIG. The linear equation of the approximate straight line was y=3.1760x. Also, the R2 value indicating linearity was 1.0000.

Based on these, Table 24 shows the results of estimating general lattice constants of the FT substance group. Here, n = 1, 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, 28, respectively 1/1 crystal, 4/5 crystals, 5/6 crystals, 6/7 crystals, 7/8 crystals, 8/9 crystals, 9/11 crystals, 11/13 crystals, 13/15 crystals, 13/16 crystals, 14/17 crystals, 16/19 crystals Lattice constant c of crystal, 17/20 crystal, 17/21 crystal, 19/23 crystal, 22/27 crystal, and 23/28 crystal is shown.

[Composition in FT substance group]
Table 25 shows the compositions obtained from structural analysis of Examples 2 and 3 and the calculated compositions obtained from EDX measurements of Reference Example 1, Example 1, Example 4 and Example 5.

As shown in Table 25, solid solution of Mg is conspicuously observed in Reference Example 1, but it is considered possible in other FT substance groups. In addition, it is considered possible to adjust the N, O composition ratio in any of the FT substance groups. Furthermore, it is conceivable that halogen elements such as F and Cl are contained as some impurities.

The phosphor of the present invention has a crystal structure and emission characteristics different from those of conventional phosphors, and emits green to yellow light by near-ultraviolet or short-wavelength visible light. and can be widely and effectively used as a fluorescent material used in various applications such as image display devices.

Claims (30)

M element, A element, Li, and C element (where M element is an activating element, A element is at least one element selected from the group consisting of Ca, Sr, and Ba, C element is Al and/or is Ga) and further comprises a crystalline phase having N and / or O,
In the crystal phase, the lattice constant satisfies the following range, the crystal system is tetragonal,
7.10≦lattice constant a≦8.68
7.10≤lattice constant b≤8.68
2.86×n≦lattice constant c≦3.49×n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28 Note that the ranges of lattice constants c specified by n may overlap.)
Furthermore, fluorescence characterized by containing a crystal phase represented by the following formula [1] that can contain an E element (wherein the E element is at least one or more elements selected from the group consisting of Si and Ge) body.
M _a A _1-a Li _b-d1 C _c-d2-e Mg _d1+d2 E _e N _f O _g [1]
(In formula [1] above, a, b, c, d1, d2, e, f, and g are values that independently satisfy the following formula.
0<a≦0.2
1.0≤b≤3.5
1.0≤c≤4.0
0≦d1≦3.5
0≤d2≤4.0
0≤e≤4.0
0≤f≤5.0
0≤g≤5.0
4.0≤b+c≤5.0
4.0≤f+g≤5.0
0≦b−d1
0≦c−d2−e
0≦d1+d2≦0.6) 2. The phosphor according to claim 1, wherein at least Li and C elements are present in the same crystal site. 3. The phosphor according to claim 1, further comprising Mg and/or E elements. Any one of claims 1 to 3, wherein 0 ≤ d1 ≤ 0.6, 0 ≤ d2 ≤ 0.6, and 0 ≤ e ≤ 1.0 in the above formula [1] The phosphor according to the item. 5. The phosphor according to any one of claims 1 to 4, wherein 4.5 ≤ b + c ≤ 5.0 and 4.5 ≤ f + g ≤ 5.0 in the formula [1]. . 6. The phosphor according to any one of claims 1 to 5, wherein the crystal phase includes a crystal phase represented by the following formula [2].
M _a' A _m/na' Li _x-y1 C _4-x-y2-z Mg _y1+y2 E _z N _{4+2m/
n-2x+y1-y2+z} O _{2x-y1+y2-z-2m/n} [2]
(In formula [2] above, a', m, n, x, y1, y2, and z are values that independently satisfy the following formula.
0<a′≦0.2×m/n
4/5≦m/n≦8/9
m/n≤x≤2+m/n
0≤y1≤0.6
0≤y2≤0.6
0≤y1+y2≤0.1
0≤z≤1.0
0≦x−y
0≦4-xy2-z) The fluorescence according to any one of claims 1 to 6, wherein the M element contains at least one element selected from the group consisting of Eu, Ce, Pr, Sm, Tb, Dy and Yb. body. Any one of claims 1 to 7, wherein n is an integer selected from 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, and 28 or the phosphor according to item 1. 22/27 ≤ m/n ≤ 7/8 and 0.5 × m/n + 0.5 × (2 + m/n) ≤ x ≤ 2 + m/n in the above formula [2] The phosphor according to claim 6 or any one of claims 7 to 8 reciting at least claim 6. The phosphor according to any one of claims 6 and 7 to 9, wherein 0≦z≦0.1 in the formula [2]. The phosphor according to any one of claims 1 to 10, wherein the M element contains Eu, the A element contains Sr, and the C element contains Al. 12. The phosphor according to any one of claims 1 to 11, wherein the E element contains Si. 13. The phosphor according to any one of claims 1 to 12, wherein n is an integer selected from 6, 7, 13, 17 and 23. 14/17 ≤ m/n ≤ 6/7 and 0.25 × m/n + 0.75 × (2 + m/n) ≤ x ≤ 2 + m/n in the above formula [2] The phosphor according to claim 6 or any one of claims 7 to 13, which at least relies on claim 6. The phosphor according to any one of claims 1 to 14, wherein the M element contains Eu, the A element contains Sr, the C element contains Al, and the E element contains Si. In the above formula [2], n is 6, and 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n. 16. The phosphor according to any one of claims 7 to 15 citing 6. 17. The phosphor according to claim 16, wherein m is 5 and n is 6 in the formula [2]. In the above formula [2], n is 7, and 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n 6 or at least claim 16. The phosphor according to any one of claims 7 to 15 citing 6. 19. The phosphor according to claim 18, wherein m is 6 and n is 7 in the formula [2]. In the above formula [2], n is 13, and 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n 6 or at least claim 16. The phosphor according to any one of claims 7 to 15 citing 6. 21. The phosphor according to claim 20, wherein m is 11 and n is 13 in the formula [2]. In the above formula [2], n is 17, and 0.05 × m / n + 0.95 × (2 + m / n) ≤ x ≤ 2 + m / n 6 or at least claim 16. The phosphor according to any one of claims 7 to 15 citing 6. 23. The phosphor according to claim 22, wherein m is 14 and n is 17 in the formula [2]. In the above formula [2], n is 23, and 0.05×m/n+0.95×(2+m/n)≦x≦2+m/n. 16. The phosphor according to any one of claims 7 to 15 citing 6. 25. The phosphor according to claim 24, wherein m is 19 and n is 23 in the formula [2]. further comprising F and/or Cl;
26. The phosphor according to any one of claims 1 to 25, wherein the total content of F and Cl in terms of elemental amounts is 5000 ppm or less. A phosphor composition comprising the phosphor according to any one of claims 1 to 26, wherein the phosphor is contained in an amount of 20% by mass or more with respect to the total amount. At least an excitation light source that emits light in the near-ultraviolet or short-wavelength visible region, and a phosphor that converts at least part of the light emitted by the excitation light source into a different emission spectrum,
The phosphor comprises at least the phosphor according to any one of claims 1 to 26 and / or the phosphor composition according to claim 27,
Luminescent device. characterized by comprising the light emitting device according to claim 28,
lighting device. characterized by comprising the light emitting device according to claim 28,
Image display device.

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